1. Field of the Invention
The present invention relates to an auxiliary apparatus used in pressing work, and more particularly to a lifting apparatus for transporting material into a die in a press machine and for taking a product out of the die.
2. Description of the Prior Art
Throwing or carrying machines are commonly employed as a substitute for human labor in transporting objects such as material or semi-processed goods into a press die and in taking the object workpiece out of the die after each press work is finished. This kind of machine generally consists of two components, namely, a lifting apparatus for supporting and moving an object in up-and-down fashion and an apparatus for moving the lifting apparatus in the horizontal direction to position the workpiece within a press die and to remove it therefrom. Such a lifting apparatus commonly has arm portions for supporting a workpiece which is transferred from the preceding step. After the press work step is completed, the arm portions lift up and support the workpiece. If, as has been the case in the prior art, the arm portions are made of a specific material such as metal alone, the workpiece may be damaged, since the workpiece is unstable relative to the supporting arm, and can slip and be deformed from resulting impacts. Attempts have been made to attach rubber rollers to enable the arm portions to securely receive workpieces with the assistance of frictional force of rubber acting on the same. However, the ability of rubber rollers to perform this function is generally not sufficient to satisfactorily stabilize workpieces and prevent their deformations.